Immunoglobulin EImmunoglobulinImmunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig)
"isotype") that has only been found in mammals. IgE is synthesised by
plasma cells. Monomers of IgE consist of two heavy chains (ε chain)
and two light chains, with the ε chain containing 4 Ig-like constant
domains (Cε1-Cε4).[1] IgE's main function is immunity to parasites
such as helminths[2] like Schistosoma mansoni, Trichinella spiralis,
and Fasciola hepatica.[3][4][5] IgE is utilized during immune defense
against certain protozoan parasites such as Plasmodium falciparum.[6]
IgE also has an essential role in type I hypersensitivity,[7] which
manifests in various allergic diseases, such as allergic asthma, most
types of sinusitis, allergic rhinitis, food allergies, and specific
types of chronic urticaria and atopic dermatitis
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Fc Receptor
An
Fc receptorFc receptor is a protein found on the surface of certain
cells – including, among others, B lymphocytes, follicular
dendritic cells, natural killer cells, macrophages, neutrophils,
eosinophils, basophils, human platelets, and mast cells – that
contribute to the protective functions of the immune system. Its name
is derived from its binding specificity for a part of an antibody
known as the Fc (Fragment, crystallizable) region. Fc receptors bind
to antibodies that are attached to infected cells or invading
pathogens. Their activity stimulates phagocytic or cytotoxic cells to
destroy microbes, or infected cells by antibody-mediated phagocytosis
or antibody-dependent cell-mediated cytotoxicity
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Basophil
Basophils are a type of white blood cells. Basophils are the least
common of the granulocytes, representing about 0.5 to 1% of
circulating white blood cells.[2] However, they are the largest type
of granulocyte. They are responsible for inflammatory reactions during
immune response, as well as in the formation of acute and chronic
allergic diseases, including anaphylaxis, asthma, atopic dermatitis
and hay fever.[3] They can perform phagocytosis (cell eating), produce
histamine and serotonin that induce inflammation, and heparin that
prevents blood clotting[4], although there are less than that found in
Mast cellMast cell granules[5]
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Eosinophil
Eosinophils sometimes called eosinophiles or, less commonly,
acidophils, are a variety of white blood cells and one of the immune
system components responsible for combating multicellular parasites
and certain infections in vertebrates.[citation needed] Along with
mast cells and basophils, they also control mechanisms associated with
allergy and asthma
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Monocyte
Monocytes are a type of leukocyte, or white blood cell. They are the
largest type of leukocyte and can differentiate into macrophages and
myeloid lineage dendritic cells. As a part of the vertebrate innate
immune system monocytes also influence the process of adaptive
immunity. There are at least three subclasses of monocytes in human
blood based on their phenotypic receptors.Contents1 Structure1.1 Subpopulations2 Development2.1 Dendritic cells3 Function
4 Clinical significance4.1 Monocytosis
4.2 Monocytopenia
4.3
BloodBlood content5 See also
6 References
7 External linksStructure[edit]
Monocytes are amoeboid in appearance, and have a granulated
cytoplasm.[1] Containing unilobar nuclei, these cells are one of the
types of mononuclear leukocytes which shelter azurophil granules
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Macrophage
Macrophages (Greek: big eaters, from Greek μακρός (makrós) =
large, φαγείν (phageín) = to eat[1]) are a type of white blood
cell, of the immune system, that engulfs and digests cellular debris,
foreign substances, microbes, cancer cells, and anything else that
does not have the type of proteins specific to healthy body cells on
its surface[2] in a process called phagocytosis. These large
phagocytes are found in essentially all tissues,[3] where they patrol
for potential pathogens by amoeboid movement. They take various forms
(with various names) throughout the body (e.g., histiocytes, Kupffer
cells, alveolar macrophages, microglia, and others), but all are part
of the mononuclear phagocyte system. Besides phagocytosis, they play a
critical role in nonspecific defense (innate immunity) and also help
initiate specific defense mechanisms (adaptive immunity) by recruiting
other immune cells such as lymphocytes
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Platelet
Platelets, also called thrombocytes (thromb- + -cyte, "blood clot
cell"), are a component of blood whose function (along with the
coagulation factors) is to stop bleeding by clumping and clotting
blood vessel injuries.[1] Platelets have no cell nucleus: they are
fragments of cytoplasm that are derived from the megakaryocytes[2] of
the bone marrow, and then enter the circulation. These unactivated
platelets are biconvex discoid (lens-shaped) structures,[3][4]
2–3 µm in greatest diameter.[5] Platelets are found only in
mammals, whereas in other animals (e.g. birds, amphibians)
thrombocytes circulate as intact mononuclear cells.[6]The ligands, denoted by letter L, signal for platelets (P) to migrate
towards the wound (Site A). As more platelets gather around the
opening, they produce more ligands to amplify the response
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Basophil Granulocyte
Basophils are a type of white blood cells. Basophils are the least
common of the granulocytes, representing about 0.5 to 1% of
circulating white blood cells.[2] However, they are the largest type
of granulocyte. They are responsible for inflammatory reactions during
immune response, as well as in the formation of acute and chronic
allergic diseases, including anaphylaxis, asthma, atopic dermatitis
and hay fever.[3] They can perform phagocytosis (cell eating), produce
histamine and serotonin that induce inflammation, and heparin that
prevents blood clotting[4], although there are less than that found in
Mast cellMast cell granules[5]
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Adaptive Immune Response
The adaptive immune system, also known as the acquired immune system
or, more rarely, as the specific immune system, is a subsystem of the
overall immune system that is composed of highly specialized, systemic
cells and processes that eliminate pathogens or prevent their growth.
The adaptive immune system is one of the two main immunity strategies
found in vertebrates (the other being the innate immune system).
Adaptive immunity creates immunological memory after an initial
response to a specific pathogen, and leads to an enhanced response to
subsequent encounters with that pathogen. This process of acquired
immunity is the basis of vaccination. Like the innate system, the
adaptive system includes both humoral immunity components and
cell-mediated immunity components.
Unlike the innate immune system, the adaptive immune system is highly
specific to a particular pathogen
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Dendritic Cells
Dendritic cells (DCs) are antigen-presenting cells (also known as
accessory cells) of the mammalian immune system. Their main function
is to process antigen material and present it on the cell surface to
the T cells of the immune system. They act as messengers between the
innate and the adaptive immune systems.
Dendritic cells are present in those tissues that are in contact with
the external environment, such as the skin (where there is a
specialized dendritic cell type called the Langerhans cell) and the
inner lining of the nose, lungs, stomach and intestines. They can also
be found in an immature state in the blood. Once activated, they
migrate to the lymph nodes where they interact with T cells and B
cells to initiate and shape the adaptive immune response. At certain
development stages they grow branched projections, the dendrites that
give the cell its name (δένδρον or déndron being Greek for
"tree")
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Antigen
In immunology, an antigen is a molecule capable of inducing an immune
response (to produce an antibody) in the host organism.[1] Sometimes
antigens are part of the host itself in an autoimmune disease.[2]
AntigensAntigens are "targeted" by antibodies. Each antibody (immune response)
is specifically produced by the immune system to match an antigen
after cells in the immune system come into contact with it; this
allows a precise identification or matching of the antigen and the
initiation of a tailored response. The antibody is said to "match" the
antigen in the sense that it can bind to it due to an adaptation
performed to a region of the antibody; because of this, many different
antibodies are produced, each with specificity to bind a different
antigen while sharing the same basic structure
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